1. Field of the Invention
The present invention relates to a compressor, and more particularly to a compressor having an improved valved piston device.
2. Description of the Prior Art
Typical compressors comprise a piston slidably received in a piston housing and a sealing ring solidly engaged on the piston and engaged between the piston and the piston housing. The pistons of the typical compressors have no valves provided therein, such that the typical piston or the sealing ring may be easily damaged. In addition, a number of valve members are required for controlling the air into and out of the piston housing.
The applicant had developed various kinds of valved pistons, and issued as U.S. Pat. No. 5,655,887, to Chou, and U.S. Pat. No. 6,095,758, to Chou, and U.S. Pat. No. 6,135,725, to Chou, and comprise a complicated valved piston device for the compressors that may not be easily manufactured and assembled together and that may not be effectively operated.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional compressors.
The primary objective of the present invention is to provide a compressor including a piston device having a sealing ring loosely engaged therein for preventing the sealing ring from solidly engaging with the piston housing and for preventing the piston from being easily damaged.
The other objective of the present invention is to provide a compressor including a piston device having a number of openings and an annular groove formed therein for loosely receiving the sealing ring and for allowing the openings to be communicated with the environment when the sealing ring is loosely received in the annular groove of the piston device.
The further objective of the present invention is to provide a compressor including a piston device having a spring blade for blocking a conduit and for allowing the air to flow into the cylinder housing only and for preventing the air from flowing out of the cylinder housing.
The still further objective of the present invention is to provide a compressor including a piston device having a spring blade for blocking a number of conduits, and having a sealing ring received in an inclined outer annular groove of the piston, for forming a double security structure.
In accordance with one aspect of the invention, there is provided a valved piston device for a compressor, the valved piston device comprising a housing including a chamber formed therein, a piston slidably received in the chamber of the housing, the piston including an outer peripheral portion having an annular groove formed therein and defined by an inclined inner peripheral surface, and including an upper portion having a plurality of openings formed therein and communicating with the annular groove of the piston, and a sealing ring received in the annular groove of the piston. The inclined inner peripheral surface of the piston includes a lower portion having a diameter greater than that of the sealing ring for forming a lower portion of the annular groove of the piston and for forcing the sealing ring to engage with the housing, and includes an upper portion having a diameter less than that of the sealing ring for forming an upper portion of the annular groove of the piston and for loosely receiving the sealing ring in the upper portion of the annular groove of the piston, the openings of the piston are communicating with the annular groove of the piston and communicating with the chamber of the housing when the sealing ring is loosely received in the upper portion of the annular groove of the piston.
The housing includes a tube extended outward therefrom and includes a passage formed therein and communicating with the chamber of the housing and communicating with the tube, for allowing the air in the chamber of the housing to be forced to flow through the passage of piston and to flow through the tube when the piston is moved toward the tube.
The piston includes a plate disposed on top thereof, and means for securing the plate to the piston for defining the upper portion of the piston.
The piston further includes at least one conduit formed therein and communicating with the chamber of the housing with an environment, and a spring blade for selectively blocking the conduit of the piston and for allowing the air to flow through the conduit of the piston and to flow into the chamber of the housing when the piston is moved in a direction away from the housing.
The spring blade includes a first end or a middle or a center portion secured to the piston and includes at least one arm extended therefrom for blocking the conduit of the piston.
The conduits may be arranged in a circle in the piston. The spring blade includes a circular shape having a center portion secured to the piston and having a peripheral portion for blocking the conduits of the piston.
The openings of the piston may be opened toward a radially outer peripheral portion of the piston.